Earth-auger



{no Model.)

M. J. STOPFER.

EARTH AUGBB.

No. 598,001. Patented Nov 2, 1897.

UNITED STATES MARTIN JAY STOFFER, OF CAPAO, MICHIGAN.

EARTH-AUG ER.

SPECIFICATION forming part of Letters Patent N 0. 593,001, dated November 2, 1897.

Application filed May 27, 1897. serial No. 6 38,414. (No model.)

To all zqhmn it may concern:

Be it known that I, MARTIN JAY STOFFER, a citizen of the United States, residing at Capac, in the county of St. Clair and State of Michigan, have invented a new and useful Earth- Auger, of which the following is a specification.

My invention relates to earthaugers, and has for its object to provide a simple, inexpensive, and efficient arrangement and c0nstruction of parts whereby the cutting and the discharge of earth are facilitated.

Further objects and advantages of this invention will appear in the following description, and the novel features thereof will be particularly pointed out in the appended claims.

In the drawings, Figure 1 is a perspective view of an anger constructed in accordance with my invention, showing the parts in their closed positions. Fig. 2 is a side view showing the movable blade in the discharging position and indicating in dotted lines the raised or locked position of the operating-lever. Fig. 3 is a plan view of the head, partly in section.

Similar numerals of reference indicate corresponding parts in all the figures of the drawings.

Carried by the shank or stafi 1, which is bifurcated at its lower end, is a head comprising a circular band 2 and a plurality of blades mounted upon the band. The band is preferably constructed of a strip or plate of metal bent into circular form with its extremities inturned,as shown at 3,aud arranged at an interval equal to the thickness of the shank 4 of a movable or pivotal blade 5, said shank being mounted between the inturned extremities of the band by means of a pivotbolt 6. The head is provided with at least three blades, of which the stationary blades 7 are bolted, as shown at 8, to the band to provide for their removal to facilitate sharpening, and the movable or pivotal blade-is arranged in a plane located midway between the stationary blades to cooperate therewith in holding earth, the front edges of all of the blades being reduced and being extended downwardly and forwardly to form feedingvpoints 9.

The shank of the movable or pivotal blade is extended to form an arm 10, to which is attached an operating-lever 11 by means of a connecting-rod 12, the upward-swingin g movement of the operating-lever being limited by contact with the shank 1 and the point of connection 13 of the rod 12 with the operatinglever being in such a position with relation to the fulcrum 14 of said lever that the point 13 is closer to the plane of the shank when the lever is in the normal position (shown in Fig. 1) than is the fulcrum. Hence this constitutes a lock which prevents the movable blade from swinging outwardly during the boring operation of the tool or during the raising of earth from the hole.

The relative positions of the parts during the discharging of the contents of the augerheadare illustrated in Fig. 2, wherein the operating-lever is swung at its free end outwardly or from the shank to depress the innor end of the arm 10 and thereby swing the lower end of the said blade outwardly. The upper end of the shank is fitted with a tubu lar transverse handle or crossbar 15.

The inwardly-extending normally horizontal arm 10 of the movable blade extends diametrically inward above the plane of the band 2, through the bifurcation of the shank 1, to a point beyond said shank and terminates at a distance beyond said shank approximately equal to the distance between the pivotal point 13 of the 0perating-lever 11 and the shank, whereby the connecting-rod 12 is arranged approximately parallel with the shank in all positions of the parts. that the single connection formed by the rod 12 enables the movement of the lever 11 to be communicated directly to the arm 10 of themovable blade, and when the lever is in its normal or closed position the strain applied thereby through the connection 12 to the lever 11 is approximately parallel with the shank. Hence a very slight movement of the pivotal point 13 inward from the plane of the pivot 14: provides a sufficiently secure lock to maintain the movable blade in its normal position. It will be seen that the construction, including the connection between the operating-lever and the movable blade, is simple and direct and embodies the minimum number of movable parts and joints. Furthermore, the extension of the arm 10 of the movable blade in a diametrical position be- Hence it will be seen yond the center of the circular band or head 2 and hence beyond the shank 1 provides a long leverage in the operation of said blade, and by connecting the link 12 with the operating-lever 11 at an intermediate point of the latter and contiguous to the pivotal point 14 a still further increase of leverage is obtained. This increase of leverage is desirable from the fact that difficulty is frequently experienced in closing the movable blade or moving it to its normal position. It is obvious that these relative proportions of the parts necessitate the arrangement of the operating-lever at the opposite side of the shank from the point of mounting of the movable blade. I

Having described my invention, what I claim islpAn earth-auger'having awshank bifurcated at its lower end and attached to a head having a plurality of stationary blades, a movable blade pivotally mounted upon the head to cooperate with the stationary blades, and provided with an inwardly-extendin g diametrical arm projecting through the bifurcation of the shank and terminating at a point at the opposite side of said shank from the pivot of the movable blade, an operating-lever pivotally mounted upon the shank at the opposite side thereof from the pivotal point of the movable blade, to swing in the plane of the arm of said blade, and a connecting-rod be tween the extremity of said arm and an intermediate point of the operating-lever contiguous to its pivot, the upward-swinging movement of the operating-lever being limited by contact with the shank, and the point of connection of said rod with the lever bein g deflected toward the shank to form a lock for the movable blade when the lever is in its normal position, substantially as specified.

2. An earth-auger having a shank, a band or ring comprising a metallic strip or plate having contiguous inturned extremities, stationary blades bolted at intervals to the band, a movable blade pivotally mounted between the inturned extremities of the band and mounted upon a bolt by which the eXtremi ties of the band are connected, said movable blade being provided "with an inwardly-extending arm, and operating devices mounted upon the shank for actuating the ,movable blade, substantially as specified.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two witnesses.

MARTIN JAY STOFFER.

Witnesses:

MICH EL MEYER, Lnwrs B. PREsLEY. 

